The standard procedure for the generation of monoclonal antibodies as originally described by Köhler and Milstein in 1975 (Nature 256, 495-497) involves the fusion of sensitized murine spleen cells with murine myeloma cells in the presence of polyethyleneglycol (PEG). However, this method is rather inefficient. Usually, at best only one B-cell at 2×105 spleen cells successfully fuses. A great number of the cells are lost.
A major problem for the generation of human monoclonal antibodies is the fact that the hybridoma's generated are unstable in that they die, lose the ability to secrete antibody or stop proliferating shortly after the immortalization procedure.
Moreover, with traditional techniques only spleen cells can be used as the source of B-cells, because fusions with lymph node cells or peripheral blood cells only yield too limited a number of hybridomas or are not possible at all. Thus, a need exist for a method of producing human hybridomas that are stable.